• Title/Summary/Keyword: Machine Learning

Search Result 5,378, Processing Time 0.03 seconds

A Convergence Study of the Research Trends on Stress Urinary Incontinence using Word Embedding (워드임베딩을 활용한 복압성 요실금 관련 연구 동향에 관한 융합 연구)

  • Kim, Jun-Hee;Ahn, Sun-Hee;Gwak, Gyeong-Tae;Weon, Young-Soo;Yoo, Hwa-Ik
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.8
    • /
    • pp.1-11
    • /
    • 2021
  • The purpose of this study was to analyze the trends and characteristics of 'stress urinary incontinence' research through word frequency analysis, and their relationships were modeled using word embedding. Abstract data of 9,868 papers containing abstracts in PubMed's MEDLINE were extracted using a Python program. Then, through frequency analysis, 10 keywords were selected according to the high frequency. The similarity of words related to keywords was analyzed by Word2Vec machine learning algorithm. The locations and distances of words were visualized using the t-SNE technique, and the groups were classified and analyzed. The number of studies related to stress urinary incontinence has increased rapidly since the 1980s. The keywords used most frequently in the abstract of the paper were 'woman', 'urethra', and 'surgery'. Through Word2Vec modeling, words such as 'female', 'urge', and 'symptom' were among the words that showed the highest relevance to the keywords in the study on stress urinary incontinence. In addition, through the t-SNE technique, keywords and related words could be classified into three groups focusing on symptoms, anatomical characteristics, and surgical interventions of stress urinary incontinence. This study is the first to examine trends in stress urinary incontinence-related studies using the keyword frequency analysis and word embedding of the abstract. The results of this study can be used as a basis for future researchers to select the subject and direction of the research field related to stress urinary incontinence.

A study on the 3-step classification algorithm for the diagnosis and classification of refrigeration system failures and their types (냉동시스템 고장 진단 및 고장유형 분석을 위한 3단계 분류 알고리즘에 관한 연구)

  • Lee, Kangbae;Park, Sungho;Lee, Hui-Won;Lee, Seung-Jae;Lee, Seung-hyun
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.8
    • /
    • pp.31-37
    • /
    • 2021
  • As the size of buildings increases due to urbanization due to the development of industry, the need to purify the air and maintain a comfortable indoor environment is also increasing. With the development of monitoring technology for refrigeration systems, it has become possible to manage the amount of electricity consumed in buildings. In particular, refrigeration systems account for about 40% of power consumption in commercial buildings. Therefore, in order to develop the refrigeration system failure diagnosis algorithm in this study, the purpose of this study was to understand the structure of the refrigeration system, collect and analyze data generated during the operation of the refrigeration system, and quickly detect and classify failure situations with various types and severity . In particular, in order to improve the classification accuracy of failure types that are difficult to classify, a three-step diagnosis and classification algorithm was developed and proposed. A model based on SVM and LGBM was presented as a classification model suitable for each stage after a number of experiments and hyper-parameter optimization process. In this study, the characteristics affecting failure were preserved as much as possible, and all failure types, including refrigerant-related failures, which had been difficult in previous studies, were derived with excellent results.

Estimation of Significant Wave Heights from X-Band Radar Based on ANN Using CNN Rainfall Classifier (CNN 강우여부 분류기를 적용한 ANN 기반 X-Band 레이다 유의파고 보정)

  • Kim, Heeyeon;Ahn, Kyungmo;Oh, Chanyeong
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.33 no.3
    • /
    • pp.101-109
    • /
    • 2021
  • Wave observations using a marine X-band radar are conducted by analyzing the backscattered radar signal from sea surfaces. Wave parameters are extracted using Modulation Transfer Function obtained from 3D wave number and frequency spectra which are calculated by 3D FFT of time series of sea surface images (42 images per minute). The accuracy of estimation of the significant wave height is, therefore, critically dependent on the quality of radar images. Wave observations during Typhoon Maysak and Haishen in the summer of 2020 show large errors in the estimation of the significant wave heights. It is because of the deteriorated radar images due to raindrops falling on the sea surface. This paper presents the algorithm developed to increase the accuracy of wave heights estimation from radar images by adopting convolution neural network(CNN) which automatically classify radar images into rain and non-rain cases. Then, an algorithm for deriving the Hs is proposed by creating different ANN models and selectively applying them according to the rain or non-rain cases. The developed algorithm applied to heavy rain cases during typhoons and showed critically improved results.

Comparison of Handball Result Predictions Using Bagging and Boosting Algorithms (배깅과 부스팅 알고리즘을 이용한 핸드볼 결과 예측 비교)

  • Kim, Ji-eung;Park, Jong-chul;Kim, Tae-gyu;Lee, Hee-hwa;Ahn, Jee-Hwan
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.8
    • /
    • pp.279-286
    • /
    • 2021
  • The purpose of this study is to compare the predictive power of the Bagging and Boosting algorithm of ensemble method based on the motion information that occurs in woman handball matches and to analyze the availability of motion information. To this end, this study analyzed the predictive power of the result of 15 practice matches based on inertial motion by analyzing the predictive power of Random Forest and Adaboost algorithms. The results of the study are as follows. First, the prediction rate of the Random Forest algorithm was 66.9 ± 0.1%, and the prediction rate of the Adaboost algorithm was 65.6 ± 1.6%. Second, Random Forest predicted all of the winning results, but none of the losing results. On the other hand, the Adaboost algorithm shows 91.4% prediction of winning and 10.4% prediction of losing. Third, in the verification of the suitability of the algorithm, the Random Forest had no overfitting error, but Adaboost showed an overfitting error. Based on the results of this study, the availability of motion information is high when predicting sports events, and it was confirmed that the Random Forest algorithm was superior to the Adaboost algorithm.

Study on the Openness of International Academic Papers by Researchers in Library and Information Science Using POI (Practical Openness Index) (POI(Practical Openness Index)를 활용한 문헌정보학 연구자 국제학술논문의 개방성 연구)

  • Cho, Jane
    • Journal of Korean Library and Information Science Society
    • /
    • v.52 no.2
    • /
    • pp.25-44
    • /
    • 2021
  • In a situation where OA papers are increasing, POI, which indexes how open the research activities of individual researchers are, is drawing attention. This study investigated the existence of OA papers and the OA method published in international academic journals by domestic LIS researchers, and derived the researchers' POI based on this. In addition, by examining the relationship between the POI index and the researcher's amount of research papers, the research sub field, and the foreign co-authors, it was analyzed whether these factors are relevant to the researcher's POI. As a result, there were 492 papers by 82 researchers whose OA status and method were normally identified through Unpaywall. Second, only 20.7% of papers published in international journals were open accessed, and almost cases were gold and green methods. Third, there were many papers in text mining in medical journals, and the papers opened in the green method are open in institutional repositories of foreign co-authors or transnational subject repositories such as PMC. Third, the POI index was relatively higher for researchers in the field of informetrics, machine learning than other fields. In addition, it was analyzed that the presence or absence of overseas co-authors is related to OA.

A decision-centric impact assessment of operational performance of the Yongdam Dam, South Korea (용담댐 기존운영에 대한 의사결정중심 기후변화 영향 평가)

  • Kim, Daeha;Kim, Eunhee;Lee, Seung Cheol;Kim, Eunji;Shin, June
    • Journal of Korea Water Resources Association
    • /
    • v.55 no.3
    • /
    • pp.205-215
    • /
    • 2022
  • Amidst the global climate crisis, dam operation policies formulated under the stationary climate assumption could lead to unsatisfactory water management. In this work, we assessed status-quo performance of the Yongdam Dam in Korea under various climatic stresses in flood risk reduction and water supply reliability for 2021-2040. To this end, we employed a decision-centric framework equipped with a stochastic weather generator, a conceptual streamflow model, and a machine-learning reservoir operation rule. By imposing 294 climate perturbations to dam release simulations, we found that the current operation rule of the Yongdam dam could redundantly secure water storage, while inefficiently enhancing the supply reliability. On the other hand, flood risks were likely to increase substantially due to rising mean and variability of daily precipitation. Here, we argue that the current operation rules of the Yongdam Dam seem to be overly focused on securing water storage, and thus need to be adjusted to efficiently improve supply reliability and reduce flood risks in downstream areas.

Building the Outlier Candidate Discrimination Training Data based on Inventory for Automatic Classification of Transferred Records (이관 기록물 분류 자동화를 위한 목록 기반 이상치 판별 학습데이터 구축)

  • Jeong, Ji-Hye;Lee, Gemma;Wang, Hosung;Oh, Hyo-Jung
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.22 no.1
    • /
    • pp.43-59
    • /
    • 2022
  • Electronic public records are classified simultaneously as production, a preservation period is granted, and after a certain period, they are transferred to an archive and preserved. This study intends to find a way to improve the efficiency in classifying transferred records and maintain consistent standards. To this end, the current record classification work process carried out by the National Archives of Korea was analyzed, and problems were identified. As a way to minimize the manual work of record classification by converging the required improvement, the process of identifying outlier candidates based on a list consisting of classified information of the transferred records was proposed and systemized. Furthermore, the proposed outlier discrimination process was applied to the actual records transferred to the National Archives of Korea. The results were standardized and constructed as a training data format that can be used for machine learning in the future.

A Study on Verification of Back TranScription(BTS)-based Data Construction (Back TranScription(BTS)기반 데이터 구축 검증 연구)

  • Park, Chanjun;Seo, Jaehyung;Lee, Seolhwa;Moon, Hyeonseok;Eo, Sugyeong;Lim, Heuiseok
    • Journal of the Korea Convergence Society
    • /
    • v.12 no.11
    • /
    • pp.109-117
    • /
    • 2021
  • Recently, the use of speech-based interfaces is increasing as a means for human-computer interaction (HCI). Accordingly, interest in post-processors for correcting errors in speech recognition results is also increasing. However, a lot of human-labor is required for data construction. in order to manufacture a sequence to sequence (S2S) based speech recognition post-processor. To this end, to alleviate the limitations of the existing construction methodology, a new data construction method called Back TranScription (BTS) was proposed. BTS refers to a technology that combines TTS and STT technology to create a pseudo parallel corpus. This methodology eliminates the role of a phonetic transcriptor and can automatically generate vast amounts of training data, saving the cost. This paper verified through experiments that data should be constructed in consideration of text style and domain rather than constructing data without any criteria by extending the existing BTS research.

Domain Knowledge Incorporated Counterfactual Example-Based Explanation for Bankruptcy Prediction Model (부도예측모형에서 도메인 지식을 통합한 반사실적 예시 기반 설명력 증진 방법)

  • Cho, Soo Hyun;Shin, Kyung-shik
    • Journal of Intelligence and Information Systems
    • /
    • v.28 no.2
    • /
    • pp.307-332
    • /
    • 2022
  • One of the most intensively conducted research areas in business application study is a bankruptcy prediction model, a representative classification problem related to loan lending, investment decision making, and profitability to financial institutions. Many research demonstrated outstanding performance for bankruptcy prediction models using artificial intelligence techniques. However, since most machine learning algorithms are "black-box," AI has been identified as a prominent research topic for providing users with an explanation. Although there are many different approaches for explanations, this study focuses on explaining a bankruptcy prediction model using a counterfactual example. Users can obtain desired output from the model by using a counterfactual-based explanation, which provides an alternative case. This study introduces a counterfactual generation technique based on a genetic algorithm (GA) that leverages both domain knowledge (i.e., causal feasibility) and feature importance from a black-box model along with other critical counterfactual variables, including proximity, distribution, and sparsity. The proposed method was evaluated quantitatively and qualitatively to measure the quality and the validity.

Degree Programs in Data Science at the School of Information in the States (미국 정보 대학의 데이터사이언스 학위 현황 연구)

  • Park, Hyoungjoo
    • Journal of Korean Library and Information Science Society
    • /
    • v.53 no.2
    • /
    • pp.305-332
    • /
    • 2022
  • This preliminary study examined the degree programs in data science at the School of Information in the States. The focus of this study was the data science degrees offered at the School of Information awarded by the 64 Library and Information Science (LIS) programs accredited by the American Library Association (ALA) in 2022. In addition, this study examined the degrees, majors, minors, specialized tracks, and certificates in data science, as well as the potential careers after earning a data science degree. Overall, eight Schools of Information (iSchools) offered 12 data science degrees. Data science courses at the School of Information focus on topics such as introduction to data science, information retrieval, data mining, database, data and humanities, machine learning, metadata, research methods, data analysis and visualization, internship/capstone, ethics and security, user, policy, and curation and management. Most schools did not offer traditional LIS courses. After earning the data science degree in the School of Information, the potential careers included data scientists, data engineers and data analysts. The researcher hopes the findings of this study can be used as a starting point to discuss the directions of data science programs from the perspectives of the information field, specifically the degrees, majors, minors, specialized tracks and certificates in data science.